(Peter Kramer/AP Photo)

Former co-stars are sharing support and good wishes for "Mary Tyler Moore" star Valerie Harper, who revealed via People magazine on Wednesday that she has terminal brain cancer.

Harper said she told Mary Tyler Moore about her diagnosis earlier this week. Moore told People she is "absolutely devastated by this news."

"Valerie has given so much joy, laughter and love to the world," she said.

Their "Mary Tyler Moore Show" co-star Ed Asner commented in a statement obtained by" Entertainment Tonight," "Valerie Harper is a century plan and I have come to know her much better in my latter years and have every confidence in the world that she will shock the hell out of us and survive to keep functioning as the great talent and human that she is."

RELATED: Valerie Harper Diagnosed With Terminal Brain Cancer

Another "Mary Tyler Moore Show" alum, Betty White, is quoted by ET as saying, "Here I go wheezing on at 91 years old and this beautiful, beautiful lady is facing something far too soon. We all love her so much, and we are going to make the most of every second we can."

Fellow "Mary Tyler Moore Show" cast member Cloris Leachman wrote on Facebook, "I love and adore Valerie Harper and have every confidence that she is dealing with this very difficult information in the best way possible. She's one smart lady and I know she will handle her illness as she has handled everything else in her life…with intelligence, optimism and grace."

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Jason Bateman, who played one of Harper's sons on the 1980s sitcom "Valerie," told ET in a statement, "Valerie is someone that I've learned a great deal from. Not just comedically but also in her ability to put whomever approached her, or worked with her, completely at ease with a laugh and an energy that's intoxicating. My thoughts and love go out to her and her family."

According to People, Harper received her diagnosis on Jan. 15 after a series of tests that revealed that cancer cells had spread into the fluid surrounding her brain.

Harper, who previously battled lung cancer in 2009, started feeling discomfort in January, including numbness in her jaw during rehearsals for "Looped," her one-woman show. After three spinal taps, tests revealed the new cancer diagnosis, which is a rare form that only accounts for 2 percent of all cancers, reports People.